In addition to radars, the CANMAR EUROPE is equipped with an electronic map connected to a Differential Global Positioning System (DGPS). Analysis of the data recorded on the electronic map shows that the CANMAR EUROPE was sailing about seven metres from the middle of the channel. At the time of the occurrence, the Canadian Coast Guard's experimental DGPS network was in operation and transmitting corrections with an accuracy of 10 m or better 95 per cent of the time. Experience shows that the accuracy of the DGPS system on Lac St. Pierre is usually between one and five metres. Although the electronic map shows the CANMAR EUROPE going toward the starboard side of the channel, the possible margin of error in the accuracy of the DGPS system on Lac St-Pierre makes it impossible to determine with certainty the exact position of the collision relative to the middle of the channel.Analysis In addition to radars, the CANMAR EUROPE is equipped with an electronic map connected to a Differential Global Positioning System (DGPS). Analysis of the data recorded on the electronic map shows that the CANMAR EUROPE was sailing about seven metres from the middle of the channel. At the time of the occurrence, the Canadian Coast Guard's experimental DGPS network was in operation and transmitting corrections with an accuracy of 10 m or better 95 per cent of the time. Experience shows that the accuracy of the DGPS system on Lac St. Pierre is usually between one and five metres. Although the electronic map shows the CANMAR EUROPE going toward the starboard side of the channel, the possible margin of error in the accuracy of the DGPS system on Lac St-Pierre makes it impossible to determine with certainty the exact position of the collision relative to the middle of the channel. The pilots of the two vessels agreed, by radiotelephone, on a port-to-port meeting. Both deep-draught vessels were sailing near the middle of the channel to avoid bank suction effect. Neither vessel had posted a look-out outside. Because of restricted visibility, navigation was mainly by radar. The data recorded on the electronic map connected to the DGPS of the CANMAR EUROPE indicated that the vessel was sailing about seven metres from the middle of the channel. Because of the possible margin of error in the DGPS, it was not possible to determine the exact position of the collision relative to the middle of the channel. The bridge watches on both vessels did not assess accurately their vessel's position relative to the middle of the channel to ensure a safe meeting. The impact caused by the collision was not felt by the bridge watch of the CAST BEAR.Findings The pilots of the two vessels agreed, by radiotelephone, on a port-to-port meeting. Both deep-draught vessels were sailing near the middle of the channel to avoid bank suction effect. Neither vessel had posted a look-out outside. Because of restricted visibility, navigation was mainly by radar. The data recorded on the electronic map connected to the DGPS of the CANMAR EUROPE indicated that the vessel was sailing about seven metres from the middle of the channel. Because of the possible margin of error in the DGPS, it was not possible to determine the exact position of the collision relative to the middle of the channel. The bridge watches on both vessels did not assess accurately their vessel's position relative to the middle of the channel to ensure a safe meeting. The impact caused by the collision was not felt by the bridge watch of the CAST BEAR. A collision occurred between the CANMAR EUROPE and the CAST BEAR as the bridge watches on both vessels did not assess accurately their vessel's position to ensure a safe passing distance. Both vessels had planned to sail near the middle of the channel to avoid bank suction effect due to their deep draughts. This situation left the vessels little sea room to react in an emergency.Causes and Contributing Factors A collision occurred between the CANMAR EUROPE and the CAST BEAR as the bridge watches on both vessels did not assess accurately their vessel's position to ensure a safe passing distance. Both vessels had planned to sail near the middle of the channel to avoid bank suction effect due to their deep draughts. This situation left the vessels little sea room to react in an emergency.